/Engine/Source/Runtime/Engine/Classes/GameFramework/CharacterMovementComponent.h
Special Tick to allow custom server-side functionality on Autonomous Proxies. Called for all remote APs, including APs controlled on Listen Servers such as the hosting player's Character. If full server-side control is desired, you may need to override ControlledCharacterMove as well.
virtual void ServerAutonomousProxyTick ( float DeltaSeconds )